Patch "[PATCH -stable] arm: crypto: reduce priority of bit-sliced AES cipher" has been added to the 4.4-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    [PATCH -stable] arm: crypto: reduce priority of bit-sliced AES cipher

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     arm-crypto-reduce-priority-of-bit-sliced-aes-cipher.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From ebiggers@google.com  Sun Nov 19 11:20:08 2017
From: Eric Biggers <ebiggers@google.com>
Date: Fri, 17 Nov 2017 11:50:27 -0800
Subject: [PATCH -stable] arm: crypto: reduce priority of bit-sliced AES cipher
To: stable@vger.kernel.org
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>, linux-crypto@vger.kernel.org, Eric Biggers <ebiggers@google.com>
Message-ID: <20171117195027.88288-1-ebiggers@google.com>

From: Eric Biggers <ebiggers@google.com>

[ Not upstream because this is a minimal fix for a bug where arm32
  kernels can use a much slower implementation of AES than is actually
  available, potentially forcing vendors to disable encryption on their
  devices.]

All the aes-bs (bit-sliced) and aes-ce (cryptographic extensions)
algorithms had a priority of 300.  This is undesirable because it means
an aes-bs algorithm may be used when an aes-ce algorithm is available.
The aes-ce algorithms have much better performance (up to 10x faster).

Fix it by decreasing the priority of the aes-bs algorithms to 250.

This was fixed upstream by commit cc477bf64573 ("crypto: arm/aes -
replace bit-sliced OpenSSL NEON code"), but it was just a small part of
a complete rewrite.  This patch just fixes the priority bug for older
kernels.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 arch/arm/crypto/aesbs-glue.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/arch/arm/crypto/aesbs-glue.c
+++ b/arch/arm/crypto/aesbs-glue.c
@@ -357,7 +357,7 @@ static struct crypto_alg aesbs_algs[] =
 }, {
 	.cra_name		= "cbc(aes)",
 	.cra_driver_name	= "cbc-aes-neonbs",
-	.cra_priority		= 300,
+	.cra_priority		= 250,
 	.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
 	.cra_blocksize		= AES_BLOCK_SIZE,
 	.cra_ctxsize		= sizeof(struct async_helper_ctx),
@@ -377,7 +377,7 @@ static struct crypto_alg aesbs_algs[] =
 }, {
 	.cra_name		= "ctr(aes)",
 	.cra_driver_name	= "ctr-aes-neonbs",
-	.cra_priority		= 300,
+	.cra_priority		= 250,
 	.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
 	.cra_blocksize		= 1,
 	.cra_ctxsize		= sizeof(struct async_helper_ctx),
@@ -397,7 +397,7 @@ static struct crypto_alg aesbs_algs[] =
 }, {
 	.cra_name		= "xts(aes)",
 	.cra_driver_name	= "xts-aes-neonbs",
-	.cra_priority		= 300,
+	.cra_priority		= 250,
 	.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
 	.cra_blocksize		= AES_BLOCK_SIZE,
 	.cra_ctxsize		= sizeof(struct async_helper_ctx),


Patches currently in stable-queue which might be from ebiggers@google.com are

queue-4.4/arm-crypto-reduce-priority-of-bit-sliced-aes-cipher.patch